Fitted sheets for mattresses have long been known as one method for retaining a sheet on a mattress without requiring tedious folding of the corners. Prior art fitted sheets typically come in two main types.
A first type of fitted sheet includes an elastic band attached along the entire peripheral edge of the sheet to draw the sheet closed about the mattress, on the under side of the mattress. However, these elastic bands can wear out, and are not always effective in maintaining the sheet on the mattress.
A second type of fitted sheet utilizes generally triangular shaped panels in each corner of the sheet to form corner Dockets which hold the corners of the mattress. Such corner pockets are more commonly found with waterbed mattresses, wherein the corner of the waterbed may be lifted slightly to permit the mattress to be journaled within the corner pocket. However, corner pockets have also been found to be ineffective in securely maintaining a sheet on the mattress.
In addition, top sheets frequently become loose from under the mattress during use, and are inconvenient to tuck in and refold in making up a bed. For this reason, most waterbed bed clothes utilize a top sheet with a portion of the lower edge attached to a lower end of the fitted sheet. While this method of attaching the top sheet to the fitted sheet eliminates many of the problems associated with loose top sheets, it fails to address the inconvenience of refolding the top sheet at the lower corner to provide a finished appearance.